Endogenous Metabolite

In vitro activity: Epiandrosterone is a natural metabolite of dehydroepiandrosterone (DHEA) via the 5α-reductaseenzyme. Epiandrosterone is formed in peripheral tissues, from which it is released into the circulation and is ultimately excreted in the urine. Epiandrosterone is only a weak androgen, but it is widely recognized to inhibit the pentose phosphate pathway (PPP) and to decrease intracellular NADPH levels. Epiandrosterone attenuates NO-evoked relaxation of pulmonary artery, although it inhibits angiotensin II- and hypoxia-induced vasoconstriction in isolated lungs and relaxes isolated pulmonary arteries pre-constricted with KCl.

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The hemoprotein oxidant ferricyanide (FeCN) converts the iron of the heme on soluble guanylate cyclase (sGC) from Fe(2+) to Fe(3+), which prevents nitric oxide (NO) from binding the heme and stimulating sGC activity. This study uses FeCN to examine whether modulation of the redox status of the heme on sGC influences the relaxation of endothelium-removed bovine pulmonary arteries (BPA) to NO. Pretreatment of the homogenate of BPA with 50 microM FeCN resulted in a loss of stimulation of sGC activity by the NO donor 10 microM S-nitroso-N-acetylpenicillamine (SNAP). In the FeCN-treated homogenate reconcentrated to the enzyme levels in BPA, 100 microM NADPH restored NO stimulation of sGC, and this effect of NADPH was prevented by an inhibitor of flavoprotein electron transport, 1 microM diphenyliodonium (DPI). In BPA the relaxation to SNAP was not altered by FeCN, inhibitors of NADPH generation by the pentose phosphate pathway [250 microM 6-aminonicotinamide (6-AN) and 100 microM epiandrosterone (Epi)], or 1 microM DPI. However, the combination of FeCN with 6-AN, Epi, or DPI inhibited (P < 0.05) relaxation to SNAP without significantly altering the relaxation of BPA to forskolin. The inhibitory effects of 1 microM 1H-[1,2, 4]oxadiazolo[4,3-a]quinoxalin-1-one (a probe that appears to convert NO-heme of sGC to its Fe(3+)-heme form) on relaxation to SNAP were also enhanced by DPI. These observations suggest that a flavoprotein containing NADPH oxidoreductase may influence cGMP-mediated relaxation of BPA to NO by maintaining the heme of sGC in its Fe(2+) oxidation state. [2]

In vivo tests were performed using G-6-PD-low C57L/J mouse erythrocytes. Every other day, mice were orally administered with 450 or 900 mg/kg of tested agents including DHEA, EPI, pregnenolone (PREG) and androstanedione (ANDR) for seven days (four doses). Three hours after the final dose, mice were sacrificed. Findings from blood samples suggested that G-6-PD activity had no significant changes, which might be caused by the lack of receptor sites for the steroids on the erythrocyte membrane.

The dehydroepiandrosterone metabolite Epiandrosterone (EPI) inhibits the pentose phosphate pathway (PPP) and dilates isolated blood vessels pre-contracted by partial depolarization. We found that EPI (10-100 microM) also dose-dependently decreases left-ventricular developed pressure (LVDP), the rate of myocardial contraction (+d p /d t), and the pressure rate product (PRP); at 100 microM EPI, LVDP (131+/-9 vs 34+/-7 mmHg), +d p /dt (1515+/-94 vs 542+/-185 mmHg/s), and PRP (37870+/-2471 vs 9498+/-2375 HR x mmHg/min) were all significantly (P<0.05) reduced. EPI also elevated CPP in isolated hearts, decreased levels of myocardial NADPH and nitrite, and dose-dependently relaxed rat aortic rings pre-contracted with KCl. Electrophysiological analysis of single ventricular myocytes using whole cell clamp showed EPI to dose-dependently (100 n M-100 microM) and reversibly inhibit L-type channel currents carried by Ba2+ (IBa) (IC50=42+/-6 microM) by as much as 50%. At 30 microM, EPI shifted the steady-state inactivation curve to more negative potentials (V50=-26.6 mV vs -38.0 mV), thereby accelerating the decay of IBa during depolarization. These results suggest that EPI may act as a L-type Ca2+ channel antagonist with properties similar to those of 1,4-dihydropyridine (DHP) Ca2+ channel blockers. [1]

Cell Assay: It was reported that EPI, at concentrations from 10 to 100 mM, decreased left-ventricular developed pressure (LVDP) and myocardial contraction rate dose-dependently. In addition, EPI also increased CPP in isolated hearts, down-regulated levels of myocardial NADPH and nitrite, as well as relaxed rat aortic rings in the dose-dependent manner. Findings from whole cell clamp via electrophysiological analysis of single ventricular myocytes demonstrated that EPI could reversibly block L-type channel currents carried by Ba2+ in a dose-dependent manner with an IC50 of2 ± 6 M. Moreover, EPI, at a concentration of 30 mM, accelerated the decay of IBa during depolarization, which suggested this agent as a L-type Ca2+ channel antagonist with similar properties to those of 1, 4-dihydropyridine (DHP) Ca2+ channel blockers.

[1]. J Mol Cell Cardiol. 2002 Jun;34(6):679-88.
[2]. Am J Physiol. 1999 Dec;277(6 Pt 1):L1124-32.

Epiandrosterone is a 3beta-hydroxy steroid that is (5alpha)-androstane substituted by a beta-hydroxy group at position 3 and an oxo group at position 17. It has a role as an androgen and a human metabolite. It is a 17-oxo steroid, a 3beta-hydroxy steroid and an androstanoid. It is functionally related to a 5alpha-androstane.
Epiandrosterone has been reported in Homo sapiens with data available.
Epiandrosterone is a dehydroepiandrosterone metabolite and a precursor of testosterone and estradiol with hypolipidemic and anabolic property. Epiandrosterone, a potential neurosteroid, appears to bind to the gamma-aminobutyric acid (GABA)/benzodiazepine-receptor complex (GABA-RC), acting as a negative non-competitive modulator of GABA-RC as well as signal through the N-methyl-D-aspartate receptor. In addition this agent inhibits the pentose phosphate pathway (PPP) thereby dilating blood vessels pre-contracted by partial depolarization. Also, epiandrosterone inhibits the synthesis of thromboxane A2 in activated platelets, reduces plasma plasminogen activator inhibitor type 1 and tissue plasminogen activator antigen, increases serum levels of insulin-like growth factor 1 and increases cyclic guanosine monophosphate and nitric oxide synthesis. These effects may improve circulation in the microvasculature.
A metabolite of TESTOSTERONE or ANDROSTENEDIONE with a 3-alpha-hydroxyl group and without the double bond. The 3-beta hydroxyl isomer is epiandrosterone.

C19H30O2

290.44

290.224

481-29-8

441302

White to off-white solid powder

1.1±0.1 g/cm3

413.1±45.0 °C at 760 mmHg

172-174 °C

176.4±21.3 °C

0.0±2.2 mmHg at 25°C

1.536

3.75

1

2

0

21

459

7

C[C@]12CC[C@@H](C[C@@H]1CC[C@@H]3[C@@H]2CC[C@]4([C@H]3CCC4=O)C)O

QGXBDMJGAMFCBF-LUJOEAJASA-N

InChI=1S/C19H30O2/c1-18-9-7-13(20)11-12(18)3-4-14-15-5-6-17(21)19(15,2)10-8-16(14)18/h12-16,20H,3-11H2,1-2H3/t12-,13-,14-,15-,16-,18-,19-/m0/s1

(3S,5S,8R,9S,10S,13S,14S)-3-hydroxy-10,13-dimethyl-1,2,3,4,5,6,7,8,9,11,12,14,15,16-tetradecahydrocyclopenta[a]phenanthren-17-one

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: ≥ 5 mg/mL (17.22 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 50.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (8.61 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (8.61 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)