The androgen derivative 5alpha-androstane-3beta,17beta-diol inhibits tumor necrosis factor alpha and lipopolysaccharide induced inflammatory response in human endothelial cells and in mice aorta.
ABSTRACT An increasing body of evidence suggests that testosterone may exert beneficial effects against the development of atherosclerosis. These effects are thought to be the consequence of its conversion into estradiol and the activation of the estrogen receptors; however a direct role of androgens, such as dihydrotestosterone, has also been proposed. More recently, it has been shown that the transformation of the dihydrotestosterone to 5alpha-androstane-3alpha,17beta-diol (3alpha-diol) and 5alpha-androstane-3beta,17beta-diol (3beta-Adiol), generates two molecules unable to bind the androgen receptor, but with a high affinity for the estrogen receptors (ERs) in particular the beta isoform. As the actions of testosterone may result from the balance between androgenic and estrogenic molecules originating from its catabolism, we investigated the effects of the 3beta-Adiol on inflammatory responses in vitro in human endothelial cells and ex vivo in mice aortas.
3beta-Adiol reverts the pro-inflammatory gene expression pattern induced by TNF-alpha in HUVECs as determined by a cDNA microrray approach. Q-real-time PCR and protein array approaches confirmed that TNF-alpha-induced ICAM-1, VCAM-1 and ELAM-1 as well as MCP-1 and IL-6 induction was affected upon 3beta-Adiol pre-incubation. ICI 182780, an estrogen receptor antagonist and R,R-THC, an estrogen receptor beta antagonist, counteracted the effect of 3beta-Adiol while bicalutamide, an androgen receptor antagonist, had minor effects. 3beta-Adiol exerted a similar action on macrophages. Finally in castrated male mice, 3beta-Adiol significantly counteracted the LPS mediated mRNA induction of IL-6, ELAM-1and PECAM-1 in the aortas.
3beta-Adiol reverts in vitro the TNF-alpha and LPS induced pro-inflammatory activation of endothelial cells and macrophages. 3beta-Adiol in vivo modulates the inflammatory response induced by LPS in the arterial vascular wall.
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ABSTRACT: Biotransformation is an effective technique for the synthesis of libraries of bioactive compounds. Current study on microbial transformation of dihydrotestosterone (DHT) (1) was carried out to produce various functionalized metabolites. Microbial transformation of DHT (1) by using two fungal cultures resulted in potent butyrylcholinesterase (BChE) inhibitors. Biotransformation with Macrophomina phaseolina led to the formation of two known products, 5alpha-androstan-3beta,17beta-diol (2), and 5beta-androstan-3alpha,17beta-diol (3), while biotransformation with Gibberella fujikuroi yielded six known metabolites, 11alpha,17beta-dihydroxyandrost-4-en-3-one (4), androst-1,4-dien-3,17-dione (5), 11alpha-hydroxyandrost-4-en-3,17-dione (6), 11alpha-hydroxyandrost-1,4-dien-3,17-dione (7), 12beta-hydroxyandrost-1,4-dien-3,17-dione (8), and 16alpha-hydroxyandrost-1,4-dien-3,17-dione (9). Metabolites 2 and 3 were found to be inactive, while metabolite 4 only weakly inhibited the enzyme. Metabolites 5--7 were identified as significant inhibitors of BChE. Furthermore, predicted results from docking simulation studies were in complete agreement with experimental data. Theoretical results were found to be helpful in explaining the possible mode of action of these newly discovered potent BChE inhibitors. Compounds 8 and 9 were not evaluated for enzyme inhibition activity both in vitro and in silico, due to lack of sufficient quantities. Biotransformation of DHT (1) with two fungal cultures produced eight known metabolites. Metabolites 5--7 effectively inhibited the BChE activity. Cholinesterase inhibition is among the key strategies in the management of Alzheimer's disease (AD). The experimental findings were further validated by in silico inhibition studies and possible modes of action were deduced.Chemistry Central Journal 10/2013; 7(1):164. · 1.31 Impact Factor
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ABSTRACT: Sex steroids are commonly known for their contribution to phenotypic as well as biological reproductive sex differences mediated through classical regulation of neuroendocrine loops. However, sex steroids also have considerable impact on physiological function of non-reproductive tissues including the cerebrovasculature. Preclinical studies have shown that endogenous and exogenous administration of sex steroids significantly influences both cerebrovascular tone and brain function under normal conditions and following a pathological insult (e.g., middle cerebral artery occlusion). However, the precise mechanism(s) of how sex steroids modulate vasomotor responses and/or neurological outcomes in vivo is difficult to define since evidence based on both clinical and experimental studies has been shown to be dependent upon several variables including dose, duration of administration, presence of underlying pathologies, species, and sex. While progesterone, testosterone (TEST), and dihydrotestosterone (DHT) have all been investigated for their impact on the cerebral circulation, the effects of 17β-estradiol (E2) have been best characterized. Since recent reviews have highlighted studies reporting the actions of E2 on cerebral vascular function and health, only key points are included in this review. Conversely, less is known about the effect of androgens on the blood vessel wall, particularly in the cerebral circulation. The few studies that do address a role for androgen's modulation of cerebrovascular function under normal and pathophysiological conditions provide confounding evidence for either beneficial or detrimental effects. Therefore, the focus of this review is to highlight mechanisms associated with TEST, DHT, and its recently recognized androgen metabolite (3β-diol) on cerebrovascular function during healthy and diseased states.Pflügers Archiv - European Journal of Physiology 04/2013; · 4.87 Impact Factor
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ABSTRACT: Sulforaphane, a naturally-occurring isothiocyanate present in cruciferous vegetables, has received wide attention for its potential to improve vascular function in vitro. However, its effect in vivo and the molecular mechanism of sulforaphane at physiological concentrations remain unclear. Here, we report that a sulforaphane concentration as low as 0.5 μM significantly inhibited TNF-α-induced adhesion of monocytes to human umbilical vein endothelial cells (HUVECs), a key event in the pathogenesis of atherosclerosis both in static and under flow conditions. Such physiological concentrations of sulforaphane also significantly suppressed TNF-α-induced production of monocyte chemotactic protein-1 (MCP-1), adhesion molecule sVCAM-1 and sE-Selectin, key mediators in the regulation of enhanced endothelial cell-monocyte interaction. Furthermore, sulforaphane inhibited TNF-α-induced NF-κB transcriptional activity, IκBα degradation and subsequent NF-κB p65 nuclear translocation in endothelial cells, suggesting that sulforaphane can inhibit inflammation by suppressing NF-κB signaling. In an animal study, sulforaphane (300 ppm) in a mouse diet significantly abolished TNF-α-increased ex vivo monocyte adhesion and circulating adhesion molecules and chemokines in C57BL/6 mice. Histology showed that sulforaphane treatment significantly prevented the eruption of endothelial lining in the intima layer of the aorta and preserved elastin fibers' delicate organization as shown by Verhoeff-van Gieson staining. Immunohistochemistry studies showed that sulforaphane treatment also reduced VCAM-1 and monocytes-derived F4/80-positive macrophages in the aorta of TNF-α-treated mice. In conclusion, sulforaphane at physiological concentrations protects against TNF-α-induced vascular endothelial inflammation, in both in vitro and in vivo models. This anti-inflammatory effect of sulforaphane may be, at least in part, associated with interfering with the NF-κB pathway.The Journal of Nutritional Biochemistry. 01/2014;