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Steroid Δ4-Reductases: their Physiological Role and Significance
Published in Ronald Hobkirk, Steroid Biochemistry, 1979
Progesterone is an important intermediate in the biosynthesis of both adrenocortical and gonadal steroid hormones. It is itself an important hormone in female reproduction being secreted by the ovary in a reproducible pattern during the menstrual cycle. While the metabolism of a number of C19-steroids yields ring A reduced products with significant and different biological activities, the evidence for such with progesterone, although it exists, is far less convincing. In general, it can be stated that the Δ4-reduction of progesterone results in the formation of products which end up being reduced at the 3-ketone, giving 3-hydroxylated metabolites which in turn are conjugated with glucuronic acid and excreted, similar to the situation described for the corticoids; as stated previously, this will not be discussed in as much detail for progesterone. There is some recent evidence indicating that 5α-dihydroprogesterone may be formed in some progestin target tissues and then bind to the progestin receptors causing a biological effect. This is not as widespread a phenomenon as that which occurs for the androgens where the formation of 5α-dihydrotestosterone from testosterone is essential for the expression of androgenic activity in some target tissues.
Bioidentical hormones
Published in Climacteric, 2021
F. Z. Stanczyk, H. Matharu, S. A. Winer
Since sex steroid hormones do not have a hydroxyl group at carbon 11, they are not metabolized by 11β-hydroxysteroid dehydrogenase. However, there are reports that suggest the presence of several other steroid-metabolizing enzymes in salivary glands. In an in vitro study20, parotid and submandibular human salivary glands from women and men were homogenized and incubated with 14C-labeled progesterone or testosterone. Following an extraction step and thin-layer chromatography of the extracts, the thin-layer plates were autoradiographed and the radioactivity of the different metabolites was counted. The main metabolites found were 20α-dihydroprogesterone from progesterone and androstenedione from testosterone, which implies the presence of the enzymes 20α-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase type 2, respectively, in salivary glands.
Finasteride and androgenic alopecia; from therapeutic options to medical implications
Published in Journal of Dermatological Treatment, 2020
Ion G. Motofei, David L. Rowland, Mircea Tampa, Maria-Isabela Sarbu, Madalina-Irina Mitran, Cristina-Iulia Mitran, Anca Pantea Stoian, Camelia C. Diaconu, Stana Paunica, Simona R. Georgescu
After finasteride therapy, a number of cerebral neurosteroids remain disturbed, a condition that could explain the persistence of several symptoms after treatment cessation (sexual side effects, depression, anxiety, and cognitive complaints). Thus, decreased levels of progesterone and its corresponding metabolites (dihydroprogesterone and tetrahydroprogesterone), and increased levels of its precursor pregnenolone, have been detected in the cerebrospinal fluid of post-finasteride patients. In addition, a significant decreased level of dihydrotestosterone was registered, associated with increased levels of testosterone as well as of 3α-diol, 3β-diol, and 17β-estradiol. In plasma, studies have found a decreased level of dihydroprogesterone and increased levels for 5α-androstane-3α, 17β-diol, and 17β-estradiol (57–59).
Benzyl alcohol suppresses seizures in two different animal models
Published in Neurological Research, 2019
Yinhao Violet Wu, Junhan Liu, Ziying Chen, W.Mcintyre Burnham
It has been assumed that BnOH is an inert solvent, at least at the concentrations usually employed. We have discovered, however, that BnOH has unexpected anti-seizure effects. This discovery occurred during experiments designed to explore the effects of dihydroprogesterone (DHP) in female amygdala-kindled rats. The original study was a time–course study, we used 280 mg/kg of benzyl alcohol in our vehicle. Following up our initial experiments [4,5], we had switched to the intraperitoneal (i.p.) route, and a vehicle containing BnOH. As a control, the vehicle was tested alone, without DHP. Unexpectedly, it was found that the vehicle containing BnOH had clear-cut anti-seizure effects in the kindling model, with an ED50 of 100 mg/kg. These data are now presented as Experiment 1 (below).