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7α-Hydroxypregnenolone is an endogenous neuroactive steroid that stimulates locomotor activity. A synthesis of 7α-hydroxypregnenolone from pregnenolone, which takes advantage of an orthogonal protecting group strategy, is described. In detail, the C7-position was oxidized with CrO 3 and 3,5-dimethylpyrazole to yield a 7-keto steroid intermediate. The resulting 7-ketone was stereoselectively reduced to the 7α-hydroxy group with lithium tri- sec -butylborohydride. In contrast, reduction of the same 7-ketone intermediate with NaBH 4 resulted in primarily the 7β-hydroxy epimer. Furthermore, in an alternative route to the target compound, the 7α-hydroxy group was successfully incorporated by direct C–H allylic benzoyloxylation of pregnenolone-3-acetate with CuBr and tert -butyl peroxybenzoate followed by saponification. The disclosed syntheses to 7-oxygenated steroids are amenable to potentially obtain other biologically active sterols and steroids. [ABSTRACT FROM AUTHOR]

While not a disease entity in itself; symptoms of tinnitus (from Latin tinnio – clink) accompany a number of diseases. Tinnitus prevalence increases with age, deteriorates one’s quality of life, and may even result in suicidal behavior. Tinnitus develops in response to a variety of risk factors, otoxic substances, noise exposure, hearing disorders, and psychological alterations. Tinnitus is closely related to mood, depression, and psychological state. In the present study, we focused on alterations of the steroid metabolome and particularly neuroactive, neuroprotective, and immunomodulatory steroids in patients with tinnitus. The study group consisted of 28 patients without evidence of an organic cause of tinnitus as well as without associated diseases or the effect of ototoxic medications. All patients underwent a complete audiological assessment and laboratory tests including routine biochemical markers and quantification of circulating steroids using gas chromatography/mass spectrometry and immunoassays. To rule out a pathology in the cerebellopontine angle area, CT scan or MRI were performed. To diagnose stem lesions, evoked potentials were also measured. Pearson’s correlations and multivariate regression were used to assess any links between tinnitus intensity and frequency on the one hand, and steroid levels on the other. Results indicated a significant and consistent negative correlation between tinnitus indices and intensity of adrenal steroidogenesis. The circulating steroid metabolome including hormones and neuroactive, neuroprotective, and immunomodulatory steroids negatively correlates with the degree of tinnitus due to hypothalamo-pituitary-adrenal axis malfunction. Our results may help explain the pathophysiology of tinnitus and improve its diagnosis. However, further studies are needed to verify our postulation. [ABSTRACT FROM AUTHOR]

Abstract: During an initial study in searching for the alternative derivatives suitable for photolabeling of neuroactive steroids, perfluorobenzoates and perfluorobenzamides in position 17 of 5β-androstan-3α-ol were synthesized from the corresponding 17-hydroxy and 17-amino derivatives. After transformation into glutamates or sulfates, 17α-epimers had comparable inhibitory activity at NMDA receptors to the natural neurosteroid (20-oxo-5β-pregnan-3β-yl sulfate), however, were more potent (2- to 36-fold) than their 17β-substituted analogs. In one case, fluorine in position 4′ of perfluorobenzoate group was substituted with azide and activity of the final glutamate was retained comparing with the corresponding perfluorobenzoate. The series was expanded with perfluorobenzoyl derivatives of pregnanolone: Perfluorobenzamide of glutamate and perfluorobenzoate of 11α-hydroxy pregnanolone were prepared and tested. From nine tested compounds, four of them exhibit very good inhibition activity and can serve as promising leads for photolabeling experiments. [Copyright &y& Elsevier]

Abstract: Background: Epilepsy in women may be associated with reproductive disorders and alterations in serum steroid levels. Some steroids can be induced by epilepsy and/or treatment with antiepileptic drugs; however, there are still limited data available concerning this effect on the levels of other neuroactive steroid metabolites such as 3a-hydroxy-5a/b-reduced androstanes. Aim: To evaluate steroid alterations in women with epilepsy (WWE) on lamotrigine monotherapy. Subjects and methods: Eleven WWE and 11 age-matched healthy women underwent blood sampling in both phases of their menstrual cycles (MCs). The steroid metabolome, which included 30 unconjugated steroids, 17 steroid polar conjugates, gonadotropins, and sex hormone-binding globulin (SHBG), was measured using gas chromatography–mass spectrometry (GC–MS) and radioimmunoassay (RIA). Results: WWE had lower cortisol levels (status p <0.001), but elevated levels of unconjugated 17-hydroxypregnenolone (status p <0.001). Progesterone was higher in the follicular menstrual phase (FP) in WWE than in the controls (status×menstrual phase p <0.05, Bonferroni multiple comparisons p <0.05), whereas 17-hydroxyprogesterone was higher in WWE in both menstrual phases (status p <0.001). The steroid conjugates were mostly elevated in WWE. The levels of 5α/β-reduced androstanes in WWE that were significantly higher than the controls were etiocholanolone (status p <0.001), 5α-androstane-3α,17β-diol (status p <0.001), and the 5α/β-reduced androstane polar conjugates (status p <0.001). Conclusions: WWE showed a trend toward higher circulating 3α-hydroxy-5α/β-reduced androstanes, increased activity of 17α-hydroxylase/17,20 lyase in the Δ5-steroid metabolic pathway, and increased levels of the steroid polar conjugates. [Copyright &y& Elsevier]

Abstract: Analogs of pregnanolone (3α-hydroxy-5β-pregnan-20-one), modified in position 17 were prepared. Compounds with 20-keto pregnane side chain replaced completely by azide (17α- and 17β-azido-5β-androstan-3α-ol), compounds with its part replaced (20-azido-21-nor-5β-pregnan-3α-ol), and compounds with keto group only replaced ((20R)- and (20S)-20-azido-5β-pregnan-3α-ol) were synthesized using tosylate displacements with sodium azide or Mitsunobu reaction with azoimide. All five azido steroids were converted into corresponding sulfates. Subsequent tests for inhibition of glutamate induced response on NMDA receptors revealed that modification of pregnanolone sulfate side chain with azide did not disturb the activity and some of sulfates tested were more active than parent compound. [Copyright &y& Elsevier]

Abstract: Certain androstane steroids (AS) modulate ionotropic receptors, as do the pregnane steroids. Whereas women produce significant amounts of neuroactive progesterone metabolites, the steroid neuromodulators in men originate mainly from the 3-oxo-4-ene C19-steroids, which are converted to their 3α- and 3β-hydroxy-5α/5β-reduced metabolites. The neuromodulating effects of AS prompted us to monitor circulating levels of the steroids to estimate metabolic pathways in the periphery that may influence brain concentrations of AS. Hence, the serum levels of 20 steroids and 16 steroid polar conjugates including 17-oxo- and 17β-hydroxy-derivatives of 5α/β-androstane-3α/β-hydroxy-androstane steroids were quantified in 15 men (16–62 years of age) using GC–MS. The conjugated AS for the most part reached micromolar concentrations, these being two or three orders of magnitude higher than those of the free steroids. The ratios of conjugates to free steroids were one to two orders of magnitude higher than the values for the corresponding pregnane steroids. This data suggested that conjugation may considerably restrain the transport of free AS from the periphery into the central nervous system. [Copyright &y& Elsevier]

Abstract: Synthesis of reference standards is needed to determine the presence and function of steroid glucuronides in the brain or other tissues, because commercial sources of steroid glucuronide standards are limited or unavailable. In the present study porcine, rat, and bovine liver microsomes were tested to evaluate their ability to glucuronidate eight neurosteroids and neuroactive steroids of various types: dehydroepiandrosterone, pregnenolone, isopregnanolone, 5α-tetrahydrodeoxycorticosterone, corticosterone, cortisol, β-estradiol, and testosterone. In general, the glucuronidation efficiency of rat liver was rather poor compared with that of bovine and porcine liver microsomes. Since porcine liver apparently has a relatively large amount of dehydrogenase, its microsomes also produced dehydrogenated steroids and their glucuronides, as well as various regioisomers in which the site of glucuronidation varied. In contrast, bovine liver microsomes produced mainly a single major glucuronidation product and few dehydrogenation products and gave the best overall yield for two-third of the steroids tested. The enzymatic synthesis of five glucuronides of four steroids was carried out and the conditions, purification, and analytical methods for the glucuronidation products were optimized. The steroid glucuronides synthesized were characterized by nuclear magnetic resonance spectroscopy (NMR) and liquid chromatography–mass spectrometry (LC–MS). The stereochemically pure steroid glucuronide conjugates were recovered in milligram amounts (yield 10–78%) and good purity (>85–90%), which is sufficient for LC–MS/MS method development and analyses of steroid glucuronides in biological matrices such as brain, urine, or plasma. [Copyright &y& Elsevier]

Abstract: Long-term alcohol consumption results in menstrual irregularities due to the inhibition of progesterone secretion. Some progesterone metabolites, including three pregnanolone isomers (PI), abate, while pregnenolone sulfate (PregS) and dehydroepiandrosterone sulfate (DHEAS) increase, alcohol tolerance. The rationale of this study was to evaluate how the neuroactive steroids reflect the impaired progesterone formation in premenopausal women treated for alcohol addiction, and whether detoxification therapy could restore female reproductive functions and psychosomatic stability by reinstatement of the steroid biosynthesis. Accordingly, serum allopregnanolone (3α-hydroxy-5α-pregnan-20-one (P3α5α)), pregnanolone (P3α5β), isopregnanolone (P3β5α) and epipregnanolone (P3β5β), progesterone, PregS, pregnenolone, 17α-hydroxy-pregnenolone (Preg17), 17α-hydroxy-progesterone (Prog17), DHEA, DHEAS, cortisol and estradiol were measured in 20 women during the therapy (start, 3 days, 14 days, 1 month, 4 months), and in 17 controls, using GC-MS or RIA and evaluated by age-adjusted ANCOVA with status and phase of the menstrual cycle (PMC) as factors, and status–PMC interaction. The patients exhibited depressed progesterone, Prog17, PI, and estradiol, a decreased progesterone/pregnenolone ratio, a decreased ratio of neuroinhibiting P3α5α to neuroactivating PregS, and an elevated PregS and PregS/pregnenolone ratio. The treatment mostly restored the indices. The reduction of neuroinhibiting pregnanolone isomers in the patients is primarily associated with the impairment in ovarian steroid biosynthesis. Nevertheless, changes in enzyme activities connected with the formation of PI and the influence of altered physiological requirements on the balance between endogenous neuroinhibiting and neuroactivating steroids are also likely. The reinstatement of serum estradiol, progesterone, and PI during the therapy demonstrates its favorable effect on both reproductive functions and the psychosomatic stability of the patients. [Copyright &y& Elsevier]

The sciatic nerve, and the Schwann cells in particular, are able to synthesize progesterone and possess the enzymes forming the 5α-reduced and the 3α-5α-reduced derivatives of progesterone: dihydroprogesterone and tetrahydroprogesterone. Moreover, the progesterone receptor (PR) is present in the sciatic nerve and in Schwann cell cultures. These facts suggest that progesterone and its derivatives might play a role in the control of the synthesis of the two major proteins of the peripheral nervous system (PNS): the glycoprotein Po (Po) and peripheral myelin protein 22 (PMP22). We have shown that: (a) dihydroprogesterone enhances the low mRNA levels of Po in the sciatic nerve of aged male rats; (b) progesterone and its derivatives stimulate the gene expression of Po in the sciatic nerve of adult rats and in Schwann cell cultures; (c) tetrahydroprogesterone increases PMP22 gene expression in the sciatic nerve of adult rats and in Schwann cell cultures. In additional experiments, utilizing agonists and antagonists of PR and GABAA receptor, we have observed that progesterone and its derivatives control Po gene expression via the PR, while tetrahydroprogesterone modulates the expression of PMP22 through the GABAA receptor. [Copyright &y& Elsevier]