Progesterone receptor

In T47D cells, medroxyprogesterone (10 nM, 48 h) stimulates the production of Cyclin D1 via the PI3K/Akt signaling pathway, hence promoting cell proliferation [1]. By raising the expression of signaling molecules in HUVECs, medroxyprogesterone (100 nM, 24 h) increases the number of monocyte markers on HUVECs, which may be the cause of atherosclerosis [2].

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mRNA levels of adhesion molecules in HUVECs treated with medroxyprogesterone acetate (MPA) or 17β-estradiol + MPA were 1.7- to 2.5-fold higher than those in the control. MPA increased the protein expression of E-selectin, P-selectin, and intercellular adhesion molecule-1 compared with that for the control (83.0 ± 0.7, 34.8 ± 1.2, and 5.4 ± 0.0 ng/mL, respectively), whereas other progestogens or 17β-estradiol additive to progestogens did not significantly change expression. MPA significantly increased U937 monocytoid cell adherence compared with the control (56.0 ± 1.5 vs 46.5 ± 3.5 adherent cells per 10 fields) but did not increase adherence to HUVECs with knocked down intercellular adhesion molecule-1.
Conclusions: MPA increases cell adhesion molecule expression on HUVECs, causing increased numbers of monocytoid cells to adhere to HUVECs. These MPA effects may be a risk factor for atherogenesis on endothelial cells in postmenopausal women receiving hormone replacement therapy.[2]

Although it can enhance thrombosis, medroxyprogesterone (27.7 μg/day, subcutaneous injection) inhibits arterial vascular thrombosis [3].
MPA and MPA + E2-treated animals showed an aggravated thrombotic response shown by significantly reduced time to stable occlusion. The pro-thrombotic effect of MPA was paralleled by increased ETP whereas platelet activation was not affected. Furthermore, MPA + E2 reduced the number of cells positive for alpha-smooth muscle actin and increased hyaluronan in the plaque matrix. Interestingly, total plaque burden was reduced by MPA but unchanged by MPA + E2.[3].
Conclusion and implications: Long-term treatment with MPA and MPA + E2 increased arterial thrombosis despite inhibitory effects of MPA on atherosclerosis in ApoE-deficient mice. Increased thrombin formation, reduced smooth muscle content and remodelling of non-collagenous plaque matrix may be involved in the pro-thrombotic effects. Thus, MPA exhibits differential effects on arterial thrombosis and on atherosclerosis.[3].

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Medroxyprogesterone acetate (MPA) and MPA + E2-treated animals showed an aggravated thrombotic response shown by significantly reduced time to stable occlusion. The pro-thrombotic effect of MPA was paralleled by increased ETP whereas platelet activation was not affected. Furthermore, MPA + E2 reduced the number of cells positive for alpha-smooth muscle actin and increased hyaluronan in the plaque matrix. Interestingly, total plaque burden was reduced by MPA but unchanged by MPA + E2. Conclusion and implications: Long-term treatment with MPA and MPA + E2 increased arterial thrombosis despite inhibitory effects of MPA on atherosclerosis in ApoE-deficient mice. Increased thrombin formation, reduced smooth muscle content and remodelling of non-collagenous plaque matrix may be involved in the pro-thrombotic effects. Thus, MPA exhibits differential effects on arterial thrombosis and on atherosclerosis.[4]

The mechanism of medroxyprogesterone acetate (MPA)-induced cell proliferation in human breast cancer cells remains elusive. In this study, researchers examined the mechanism by which MPA affects the cyclin D1 expression in progesterone receptor (PR)-positive T47D human breast cancer cells. MPA (10 nM) treatment for 48 h induced proliferation of the cells (1.6-fold induction). MPA induced cyclin D1 expression (3.3-fold induction), and RU486, a selective PR antagonist, blocked the MPA-induced cell proliferation and cyclin D1 expression (23% inhibition). MPA increased both the protein level (2.2-fold induction) and promoter activity (2.7-fold induction) of cyclin D1 in MCF-7 cells transfected with PRB but not with PRA. Although MPA transcriptionally activated cyclin D1 expression, cyclin D1 promoter does not have progesterone-responsive element-related sequence. We further examined the mechanism for the regulation of the cyclin D1 expression. Because the cyclin D1 promoter contains three putative nuclear factor-kappaB (NFkappaB)-binding motifs and NFkappaB is a substrate of Akt, we investigated the effect of the phosphatidylinositol 3-kinase (PI3K)/Akt/NFkappaB cascade on the responses of cyclin D1 to MPA. MPA induced the transient phosphorylation of Akt (2.7-fold induction at 5 min), and treatment with PI3K inhibitor (wortmannin) attenuated the MPA-induced up-regulation of cyclin D1 expression (40% inhibition) and cell proliferation (40% inhibition). MPA also induced phosphorylation of inhibitor of NFkappaBalpha (IkappaBalpha) (2.3-fold induction), and treatment with wortmannin attenuated the MPA-induced IkappaBalpha phosphorylation (60% inhibition). Treatment with an IkappaBalpha phosphorylation inhibitor (BAY 11-7085) or a specific NFkappaB nuclear translocation inhibitor (SN-50) attenuated the MPA-induced up-regulation of both cyclin D1 expression (80 and 50% inhibition, respectively) and cell proliferation (55 and 34% inhibition, respectively). Because MPA induced a transient phosphorylation of Akt and the cyclin D1 promoter contains no progesterone-responsive element-related sequence, the MPA-induced cell proliferation through PRB by up-regulation of cyclin D1 expression via the PI3K/Akt/NFkappaB cascade may be a nongenomic mechanism.[1]

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The fungal transformations of medroxyrogesterone (1) were investigated for the first time using Cunninghamella elegans, Trichothecium roseum, and Mucor plumbeus. The metabolites obtained are as following: 6β, 20-dihydroxymedroxyprogesterone (2), 12β-hydroxymedroxyprogesterone (3), 6β, 11β-dihydroxymedroxyprogesterone (4), 16β-hydroxymedroxyprogesterone (5), 11α, 17-dihydroxy-6α-methylpregn-4-ene-3, 20-dione (6), 11-oxo-medroxyprogesterone (7), 6α-methyl-17α-hydroxypregn-1,4-diene-3,20-dione (8), and 6β-hydroxymedroxyprogesterone (9), 15β-hydroxymedroxyprogesterone (10), 6α-methyl-17α, 11β-dihydroxy-5α-pregnan-3, 20-dione (11), 11β-hydroxymedroxyprogesterone (12), and 11α, 20-dihydroxymedroxyprogesterone (13). Among all the microbial transformed products, the newly isolated biotransformed product 13 showed the most potent activity against proliferation of SH-SY5Y cells. Compounds 12, 5, 6, 9, 11, and 3 (in descending order of activity) also showed some extent of activity against SH-SY5Y tumour cell line. The never been reported biotransformed product, 2, showed the most potent inhibitory activity against acetylcholinesterase. Molecular modelling studies were carried out to understand the observed experimental activities, and also to obtain more information on the binding mode and the interactions between the biotransformed products, and enzyme.[4]

Cell Proliferation Assay[1]
Cell Types: T47D
Tested Concentrations: 10 nM
Incubation Duration: 24 h, 48 h, 72h
Experimental Results: Increased cell number at 48 hrs (hours).

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Western Blot Analysis [1]
Cell Types: T47D
Tested Concentrations: 10 nM
Incubation Duration: 4 h
Experimental Results: Induced Cyclin D1 protein expression.

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RT-PCR[2]
Cell Types: HUVEC
Tested Concentrations: 100 nM
Incubation Duration: 24 hrs (hours)
Experimental Results: Increased mRNA and protein expression of adhesion molecules.

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In HUVECs, adhesion molecule mRNA levels were measured by real-time PCR. Protein expression was quantified by immunocytochemistry and ELISAs. To mimic the monocyte adherence to endothelial cells, we used a flow chamber system to assess progestogen effects on U937 monocytoid cell adherence to HUVEC monolayers. We also examined the suppression effects of adhesion molecules with small interference RNAs.[2]

Animal/Disease Models: ApoE-/- mouse model [3]
Doses: 27.7 μg/day
Route of Administration: sc
Experimental Results: diminished atherosclerotic plaque and increased thrombosis.

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Apolipoprotein E (ApoE)-/- mice were bilaterally ovariectomized and treated with placebo, MPA (27.7 microg day(-1)) and MPA + 17-beta-oestradiol (E2; 1.1 microg day(-1)) for 90 days, on a Western-type diet. Thrombotic response was measured in a photothrombosis model, platelet activation by fluorescence activated cell sorting (FACS) analysis (CD62P) and thrombin generation by the endogenous thrombin potential (ETP). Furthermore, aortic plaque burden and aortic root plaque composition were determined.[3]

Absorption, Distribution and Excretion
The absolute bioavailability of medroxyprogesterone acetate (MPA) in humans has not yet been specifically studied. MPA is rapidly absorbed from the gastrointestinal tract, reaching maximum plasma concentrations 2 to 4 hours after oral administration. Co-administration with food increases the bioavailability of MPA. Taking 10 mg of MPA immediately before or after a meal increases the Cmax of MPA by 50% to 70% and the AUC by 18% to 33%. Food does not affect the half-life of MPA. Approximately 90% of medroxyprogesterone acetate is protein-bound, primarily to albumin; MPA does not bind to sex hormone-binding globulins. Most MPA metabolites are excreted in the urine as glucuronide conjugates, with only a small amount excreted as sulfate. For more complete data on the absorption, distribution, and excretion of medroxyprogesterone (10 types), please visit the HSDB records page.

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Metabolism/Metabolites
After oral administration, MPA is extensively metabolized in the liver via hydroxylation, followed by conjugation and excretion in the urine. …MPA is almost entirely metabolized and excreted via the liver. In 14 patients with advanced liver disease, the distribution of MPA was significantly altered (reduced excretion). In patients with fatty liver, the mean percentage of intact MPA excreted in the urine within 24 hours after administration of 10 mg or 100 mg doses was 7.3% and 6.4%, respectively.

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Biological Half-Life
The elimination half-life of the oral formulation is 32 to 44 hours. /Acetate/

[1]. Medroxyprogesterone acetate induces cell proliferation through up-regulation of cyclin D1 expression via phosphatidylinositol 3-kinase/Akt/nuclear factor-kappaB cascade in human breast cancer cells. Endocrinology. 2005 Nov;146(11):4917-25.

[2]. Medroxyprogesterone acetate enhances monocyte-endothelial interaction under flow conditions by stimulating the expression of cell adhesion molecules. J Clin Endocrinol Metab. 2014 Jun;99(6):2188-97.

[3]. Differential effects of medroxyprogesterone acetate on thrombosis and atherosclerosis in mice. Br J Pharmacol. 2009 Dec;158(8):1951-60.

[4]. Medroxyprogesterone derivatives from microbial transformation as anti-proliferative agents and acetylcholineterase inhibitors (combined in vitro and in silico approaches). Steroids. 2020 Dec;164:108735.

Medroxyprogesterone is a 3-oxoΔ⁴-steroid, a pregn-4-en-3,2'-dione, with an α-hydroxyl group substituted at position 17 and a methyl group substituted at position 6. It is a contraceptive, progestin, and synthetic oral contraceptive. It is a 2'-oxosteroid, 3-oxoΔ⁴-steroid, 17α-hydroxysteroid, and tertiary α-hydroxy ketone. Medroxyprogesterone is a progestin. Medroxyprogesterone is a synthetic derivative of progesterone, administered in the form of acetate (medroxyprogesterone acetate), and has anti-estrogen activity. Like other progestins, medroxyprogesterone binds to and activates nuclear receptors, which then bind to target genes and activate transcription of those genes. As an anti-estrogen, this drug may inhibit the growth-promoting effects of estrogen on estrogen-sensitive tumor cells. (NCI04)
A synthetic progestin used in veterinary practice as an estrus regulator.

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Mechanism of Action
Medroxyprogesterone has pharmacological effects similar to those of progestins. In women with adequate endogenous estrogen, medroxyprogesterone can transform the proliferative endometrium into the secretory endometrium. Medroxyprogesterone has been shown to have mild androgenic activity in animals. Anabolic effects have also been reported, but the drug appears to lack significant estrogenic activity in humans. In animals, the drug exhibits significant adrenocorticotropic activity, but no clinically significant effects have been observed in humans. Following routine intramuscular or subcutaneous injections (e.g., 150 or 104 mg every 3 months), medroxyprogesterone suppresses the secretion of pituitary gonadotropins, thereby preventing follicle maturation and ovulation, resulting in a thinning of the endometrium; these effects have a contraceptive effect. Current evidence suggests that oral administration of routine doses (i.e., 5–10 mg once daily) of medroxyprogesterone does not produce these effects. High doses of medroxyprogesterone suppress the pituitary secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and prevent the cyclical surges of gonadotropins that occur during a normal menstrual cycle. Studies have shown that this drug acts on the hypothalamus because it does not inhibit the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) after gonadotropin-releasing hormone administration, and when used as a contraceptive, the basal concentrations of LH and FSH remain within the low normal range. Although its mechanism of action is not yet clear, medroxyprogesterone has antitumor activity against certain cancers (such as endometrial cancer and renal cell carcinoma). Progestins induce all the pharmacological responses typically produced by progesterone to varying degrees: inducing secretory changes in the endometrium, increasing basal body temperature (thermotrophic effect), causing histological changes in the vaginal epithelium, relaxing uterine smooth muscle, stimulating the growth of mammary alveolar tissue, inhibiting pituitary function, and causing withdrawal bleeding in the presence of estrogen. After binding to cytoplasmic receptor proteins, progestins are transported to the cell nucleus and form a complex within the nucleus, whose response is similar to that of estrogen. However, unlike estrogen receptors, progestins do not appear to require receptor alteration. Progesterone
Although medroxyprogesterone acetate (MPA) is used as an injectable contraceptive, hormone replacement therapy (HRT), and a treatment for certain cancers, our understanding of the steroid receptors involved in MPA's action and its target genes remains limited. Researchers have found that MPA, like dexamethasone (dex), significantly inhibits the production of tumor necrosis factor (TNF)-stimulated interleukin-6 (IL-6) protein in mouse fibroblasts (L929sA). Furthermore, MPA inhibits the IL-6 and IL-8 promoter-reporter constructs at the transcriptional level by interfering with nuclear factor κB (NF-κB) and activator protein-1 (AP-1). Moreover, similar to dexamethasone, MPA does not affect the DNA-binding activity of NF-κB. The authors also observed that MPA has a significant transcriptional activation effect on the glucocorticoid response element (GRE)-driven promoter-reporter construct in L929sA and COS-1 cells. MPA-induced glucocorticoid receptor (GR) nuclear translocation and RU486 antagonism strongly suggest that MPA's effects in these cells are at least partially mediated by GR. Researchers evaluated the transcriptional effects of MPA with progesterone and dihydrotestosterone (DHT) in human breast cancer cells. We constructed and identified a novel progesterone receptor-negative, androgen receptor-positive human breast cancer cell line, named Y-AR. Using synthetic promoter/reporter gene constructs, we performed transcriptional analyses in cells lacking or containing progesterone receptors and/or androgen receptors, and compared the endogenous gene expression profiles of progesterone, medroxyprogesterone acetate (MPA), and dihydrotestosterone (DHT). In progesterone receptor-positive cells, transient transcriptional analysis showed that MPA exerts potent progesterone effects through both progesterone receptor subtypes. Interestingly, DHT transmits signals through the progesterone receptor type B. Expression profiling of genes regulating the endogenous progesterone receptor in progesterone and MPA indicated that although MPA may have slightly higher progesterone potency than progesterone, its properties are similar to those of progesterone. To investigate the effects of MPA via the androgen receptor, we performed expression profiling analysis using Y-AR cells, comparing the expression of progesterone, MPA, and DHT. The results showed extensive overlap in gene regulation between DHT and MPA via the androgen receptor, but no overlap with progesterone. Interestingly, there was no difference between pharmacological and physiological doses of MPA, suggesting that high-dose therapeutic MPA may be redundant. Comparison of the gene regulatory profiles of MPA and progesterone indicates that the effects of MPA do not fully mimic the effects of endogenous progesterone for physiological hormone replacement therapy. …The increased risk of breast cancer and/or enhanced efficacy of cancer treatment by MPA may be partially mediated by the androgen receptor.

C22H32O3

344.48

344.235

C, 76.70; H, 9.36; O, 13.93

520-85-4

Medroxyprogesterone;520-85-4;Medroxyprogesterone-d3;162462-69-3;Medroxyprogesterone-d7; 71-58-9 (acetate)

10631

White to off-white solid powder

1.1±0.1 g/cm3

488.0±45.0 °C at 760 mmHg

220-223.5ºC

263.0±25.2 °C

0.0±2.8 mmHg at 25°C

1.554

3.38

1

3

1

25

664

7

CC([C@@]1(O)CC[C@@]2([H])[C@]3([H])C[C@H](C)C4=CC(CC[C@]4(C)[C@@]3([H])CC[C@]12C)=O)=O

FRQMUZJSZHZSGN-HBNHAYAOSA-N

InChI=1S/C22H32O3/c1-13-11-16-17(20(3)8-5-15(24)12-19(13)20)6-9-21(4)18(16)7-10-22(21,25)14(2)23/h12-13,16-18,25H,5-11H2,1-4H3/t13-,16+,17-,18-,20+,21-,22-/m0/s1

Pregn-4-ene-3,20-dione, 17-hydroxy-6-alpha-methyl-

Medroxyprogesterone; NSC 27408; Medroxyprogesteron; Medroxiprogesteronum; Medroxiprogesterona; Medroxyprogesteronum; Medrossiprogesterone; 17-Hydroxy-6alpha-methylprogesterone; NSC-27408; NSC27408;

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)

DMSO : ~50 mg/mL (~145.14 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (7.26 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.)